Non-motorized vehicle wheel replacement treads and methods

ABSTRACT

A wheel for a non-motorized vehicle (e.g., a shopping cart) can include a housing assembly and a tread assembly. The housing assembly can be configured to sealingly house electronics or other components. The tread assembly can removably mate with the housing assembly such that the electronics or other components remain closed and/or sealed within the housing assembly when the tread assembly is mated or unmated with the housing assembly.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/623,676, filed Sep. 20, 2012, titled “NON-MOTORIZED VEHICLE WHEELREPLACEMENT TREADS AND METHODS,” which claims the priority benefit under35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61/537,715,filed Sep. 22, 2011, titled “WHEEL REPLACEMENT TREADS AND METHODS,” andU.S. Provisional Patent Application No. 61/692,148, filed Aug. 22, 2012,titled “WHEEL REPLACEMENT TREADS AND METHODS,” the entirety of each ofthe aforementioned applications is incorporated by reference herein.

BACKGROUND

1. Field

The present disclosure relates to replaceable treads for wheels andwheels having replaceable treads usable with non-motorized vehicles.

2. Description of the Related Art

Non-motorized wheeled vehicles, such as human-propelled carts (e.g.,shopping carts), can include two or more wheels. Vehicle wheels incurwear as a result of use or damage. For example, prolonged use of thewheel can cause a tread of the wheel to become worn down. Accordingly,the wheel may need to be replaced.

SUMMARY

Various embodiments are directed to wheels and wheel treads fornon-motorized vehicles (e.g., human-propelled carts). Replacement ofvehicle wheels can incur substantial expense, particularly inimplementations in which the vehicle wheel includes expensive electroniccomponents (e.g., theft prevention electronics in a shopping cartwheel). Accordingly, in certain embodiments, rather than replacing theentire wheel, the tread of the wheel can be replaced. In certain suchembodiments, the tread can be configured to be axially removed andinstalled on the wheel.

Certain wheels require complete or substantially complete removal and/ordisassembly of the wheel from the wheeled vehicle in order to replacethe treads of the wheels. Furthermore, some wheels may require thedisassembly of a sealed portion of the wheel in order to replace thetread. For example, some embodiments may require the opening of achamber (e.g., in a central portion of the wheel) in order to replacethe tread. However, in certain instances, it can be desirable to avoiddisassembling certain portions of the wheel to replace the tread. Forexample, it can be beneficial to avoid opening a sealed chambercontaining electrical components disposed in the wheel.

In some embodiments, a wheel assembly includes a serviceable treadassembly that is capable of being installed and attached to anon-serviceable housing assembly. As used herein, the term “serviceable”has its ordinary meaning and includes, without limitation, thecharacteristic of being intended to be replaced during the course of useof the item. As used herein, the term “non-serviceable” has its ordinarymeaning and includes, without limitation, the characteristic of notintended to be replaced during the intended course of use of the item.For example, certain components of the wheel may be sealed (e.g., toinhibit contamination) and may be non-serviceable. Non-serviceable alsoincludes situations where a component is not intended to be serviced byan end-user but which may be serviced by a factory-authorized technicianor by the manufacturer. In certain instances, the wheel assembly isconfigured for use on a non-motorized vehicle. For example, the wheelassembly can be configured for use on a locking shopping cart wheel. Insome embodiments, the tread assembly attaches to the housing assemblywith one or more fastening devices (such as screws, bolts, nails, orotherwise) and/or locking features. In certain configurations, thefastening devices and/or locking features are arranged around thecircumference of the tread assembly and/or the housing assembly.

In some embodiments, the tread assembly includes a tread and a frame(e.g., support, backbone, lattice, skeleton, spine, or other structuralportion). In certain instances, the frame provides support and/orreinforcement for the tread. For example, in certain variants, the framecan be positioned radially inward of the tread and can be configured tobear force (e.g., compressive force) that is applied to the tread. Insome implementations, the frame is configured to shape the tread (e.g.,a generally cylindrical shape). In certain embodiments, the treadassembly couples with the housing assembly, which can include a hub anda cover. In some embodiments, installation of the tread assembly isfacilitated by the structure of the hub and cover components. Forexample, the hub and cover components can be configured to allow thetread assembly to be slid onto the hub.

In certain embodiments, the tread assembly is held in position on thehousing assembly by one or more fastening devices and/or lockingfeatures. In some cases, the fastening devices and/or locking featuresare integral with the tread assembly and/or the housing assembly. Incertain embodiments, the fastening devices and/or locking features areaxially arranged around the inside and/or outside surfaces of the treadassembly and correspond to mating features similarly arranged around theouter circumferential surfaces of the wheel assembly (e.g., the hub). Asused herein, the term “axial,” or derivations thereof, has its ordinarymeaning and refers to, without limitation, a direction that issubstantially perpendicular to a plane in which the wheel rotates. Theaxial direction may be substantially parallel to or substantiallycollinear with a rotation axis of the wheel (e.g., within ten to twentydegrees of the rotation axis). In some cases, the tread assembly ismaintained on the housing assembly by one or more fasteners.

In some embodiments, the tread assembly is configured to be removed fromthe housing assembly. In certain such cases, the tread assembly can beremoved without the need to disassemble the housing assembly (e.g., byseparating the hub and the cover). Such a configuration can, forexample, facilitate easy replacement of the tread assembly (e.g., due towear or damage) while preserving the integrity of the housing assembly.For example, a tread assembly that can be replaced without the need toopen the housing assembly can maintain the efficiency of the seals onembodiments of the housing assembly that include such seals to protectcomponents (e.g., electronics) located inside the housing assembly. Incertain instances, removal of the worn or damaged tread is accomplishedby the removal or disengagement of the fastening devices and/or lockingfeatures that secure the tread to the housing assembly. In some cases,the removal also includes axially sliding the tread off the mating wheelhub exterior geometry. A new tread assembly can be installed byreversing this procedure.

A wheel for a human-propelled cart can comprise a housing assemblyhaving a hub and a cover. The hub can have an inner cavity and cancomprise a frame engaging surface having a first mating feature, theinner cavity configured to receive an electrical component and the coverconfigured to be sealed with the hub, thereby inhibiting access into theinner cavity. In some embodiments, the wheel includes a tread assemblyconfigured to axially receive a portion of the housing assembly, thetread assembly comprising a frame and a tread. The frame can have atread engaging surface and a hub engaging surface, the hub engagingsurface having a second mating feature and being configured toreleasably couple with the frame engaging surface of the hub. The treadcan be disposed radially outward of the frame and can be configured toengage a surface on which the wheel is configured to roll. The wheel caninclude a fastener configured to engage the first mating feature and thesecond mating feature. According to some variants, the tread assembly isconfigured to removably couple with the housing assembly such that thetread assembly can be axially separated from the housing assemblywithout unsealing the cover and the hub, thereby facilitating repair orreplacement of the tread assembly while maintaining the seal of thecover and the hub. In some embodiments, when the hub engaging surface ofthe frame is coupled with the frame engaging surface of the hub, thefirst mating feature and the second mating feature are circumferentiallyaligned such that the fastener can axially engage the first matingfeature and the second mating feature.

In some embodiments, at least one of the first mating feature and thesecond mating feature comprises a radially outwardly-extending flange.The tread assembly can include a frame alignment feature comprising afirst tread recess configured to receive the first mating feature. Thehousing assembly may include a hub alignment feature comprising a firsthousing recess configured to receive the second mating feature. In someembodiments, the wheel is configured to rotate around a rotation axis,and the hub is configured to be rotated relative to the frame about therotation axis of the wheel. The frame alignment feature can include asecond tread recess oriented substantially perpendicular to andextending generally circumferentially from the first tread recess, thesecond tread recess being configured to receive the first mating featurewhen the hub is rotated relative to the frame. The frame alignmentfeature can include a third tread recess extending in a directiongenerally axially away from the second mating feature, the third treadrecess configured to receive the first mating feature when the hub isrotated relative to the frame such that the first mating feature isgenerally aligned with the third tread recess. In some embodiments, thehub alignment feature includes a second housing recess generallyperpendicular to and extending generally tangentially from the firsthousing recess, the second housing recess configured to receive thesecond mating feature when the hub is rotated relative to the frame. Thehub alignment feature includes a third housing recess extending in adirection generally axially away from the first mating feature, thethird housing recess configured to receive the second mating featurewhen the hub is rotated relative to the frame such that the secondmating feature is generally aligned with the third housing recess.

In some embodiments, the tread assembly comprises a first rotationalaxis and the housing assembly comprises a second rotational axis, thefirst rotational axis and the second rotational axis being generallycollinear when the housing assembly and tread assembly are coupled. Thetread can have a tread width, the first mating feature and the secondmating feature each can have an axial width that is less than the treadwidth, and the sum of the axial widths of the first mating feature andthe second mating feature can be about equal to the tread width. In someembodiments, the human-propelled cart is a shopping cart.

A method of assembling a shopping cart wheel can comprise forming ahousing assembly. Forming the housing assembly can include providing ahub having a central cavity, the hub comprising a first mating feature,axially joining a cover with the hub, the cover configured to form aseal between the cover and the hub, thereby inhibiting access bycontaminants into the cavity, forming a tread assembly, wherein formingthe tread assembly comprises, providing an annular frame comprising aninner surface and outer surface, the inner surface and the outer surfaceeach comprising recesses, the inner surface further comprising a secondmating feature, disposing a tread around at least the outer surface ofthe frame, and engaging the tread with the recesses on the inner surfaceand the outer surface of the frame, thereby securing the tread with theframe. In some embodiments, the method of assembling a shopping cartwheel includes aligning the first mating feature of the hub with thesecond mating feature of the frame, receiving the housing assembly intothe tread assembly, and securing the housing assembly with the treadassembly.

In some embodiments, securing the housing assembly with the treadassembly comprises positioning the first mating feature in a firstrecess of the frame, wherein the first mating feature comprises aradially outwardly extending flange, positioning the second matingfeature in a second recess of the hub, wherein the second mating featurecomprises a radially inwardly extending flange, and axially inserting afastener through the first mating feature and the second mating feature.In some embodiments, the method of assembling a shopping cart wheelfurther comprises rotating the housing assembly and the tread assemblyrelative to each other after the housing assembly has been received intothe tread assembly. The method of assembling a shopping cart wheel canfurther comprise axially spacing the first mating feature apart from thesecond mating feature.

A method of repairing a wheel of a shopping cart, the wheel comprising ahousing assembly and a tread assembly coupled with a plurality offasteners located generally around an outer circumferential region ofthe wheel, the housing assembly coupled with the shopping cart via acaster assembly, the housing assembly comprising a central sealedchamber that includes an electrical component, can comprise removing thewheel from the caster assembly. In some embodiments the method ofrepairing a wheel of a shopping cart includes loosening the fastenerssuch that the housing assembly and the tread assembly can be separated,separating the tread axially from the housing assembly without openingthe central sealed chamber of the housing assembly, aligning firstflanges of a replacement tread assembly with first recesses of thehousing assembly, aligning second recesses of the replacement treadassembly with second flanges of the housing assembly, axially slidingthe replacement tread assembly onto the housing assembly, securing thefasteners such that the fasteners couple the replacement tread assemblyand the housing assembly, and coupling the housing with the casterassembly.

In some embodiments, loosening the fasteners comprises rotating thefasteners. The method of repairing a wheel of a shopping cart canfurther comprise rotating the tread assembly relative to the housingassembly after the replacement tread assembly has been axially slid ontothe housing assembly. In some embodiments, the method of repairing awheel of a shopping cart further comprising radially engaging the firstflanges of a replacement tread assembly with the first recesses of thehousing assembly, and radially engaging the second recesses of thereplacement tread assembly with the second flanges of the housingassembly, thereby providing areas of radial interference between thehousing assembly and the tread assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view of an example of a wheel assemblyfor a cart, including examples of a tread assembly and a housingassembly.

FIG. 2 illustrates a front perspective view of the tread assembly ofFIG. 1.

FIG. 2A illustrates a rear perspective view of the tread assembly ofFIG. 1.

FIG. 3 illustrates an exploded view of the tread assembly of FIG. 1,including a tread and a frame.

FIG. 4 illustrates a close-up view of a portion of the frame of FIG. 3.

FIG. 5 illustrates another close-up view of a portion of the frame ofFIG. 3.

FIG. 6 illustrates an embodiment of the housing assembly of FIG. 1,including a hub and a cover.

FIG. 7 illustrates a close-up view of a portion of the housing assemblyof FIG. 6.

FIG. 8 illustrates a close-up view of a portion of an embodiment of thehub of FIG. 6.

FIG. 9 illustrates a close-up view of a portion of an embodiment of thecover of FIG. 6.

FIG. 10 illustrates an exploded view of an embodiment of the wheelassembly of FIG. 1, including the tread assembly of FIG. 2 and thehousing assembly of FIG. 6.

FIG. 11 illustrates the wheel assembly of FIG. 10 in a partiallyassembled state, with the tread assembly coupled with the housingassembly, and a plurality of fasteners in an exploded view.

FIG. 12 illustrates the wheel assembly of FIG. 11 in an assembled state,with a caster and associated hardware shown in an exploded view.

FIG. 13 illustrates an exploded view of another embodiment of a treadassembly, including a frame and a tread.

FIG. 14 illustrates the tread assembly of FIG. 13 in an assembled state.

FIG. 15 illustrates an embodiment of a wheel hub assembly.

FIG. 16 illustrates a close-up view of the hub assembly of FIG. 15.

FIG. 17 illustrates an exploded view of the tread assembly of FIG. 14and the wheel hub assembly of FIG. 16.

FIG. 18 illustrates a close-up view of protrusions and recesses of theframe of FIG. 13.

FIG. 19 illustrates a close-up view of protrusions and recesses of thewheel hub of FIG. 15.

FIG. 20 illustrates a close-up view of one of the protrusions of FIG. 19and one of the recesses of FIG. 18 in a partially assembled state.

FIG. 21 illustrates a close-up view of the protrusion and recesses ofFIG. 20 in another partially assembled state.

FIG. 22 illustrates a close-up view of the protrusion and recesses ofFIG. 20 in an assembled state.

DETAILED DESCRIPTION

Non-motorized wheeled vehicles are used in a variety of environmentsincluding retail environments (e.g., shopping carts), manufacturing orwarehouse environments (e.g., merchandise or industrial carts), travelenvironments (e.g., luggage or baggage carts at an airport or busstation), medical environments (e.g., hospital carts, medical devicecarts, wheelchairs, baby strollers), and so forth. Non-motorizedvehicles are typically human-propelled, e.g., by a human pushing orpulling the vehicle. The present disclosure describes examples ofwheels, treads, and methods for assembling wheels or replacing treadsthat are usable with non-motorized wheeled vehicles. Many of theexamples described herein are in the context of wheels for shoppingcarts; however, this is intended for facilitating understanding and isnot a limitation.

With reference to FIG. 1, in some embodiments, a wheel assembly caninclude a tread assembly 10 and a housing assembly 70. The treadassembly 10 can be configured to mount or otherwise be received at leastpartly on the housing assembly 70. The tread assembly 10 can beconfigured to protect and/or space the housing assembly 10 from asurface on which the wheel assembly rolls. For example, the treadassembly 10 can protect the housing assembly 70 from abrasion due tocontact with the surface.

With regard to FIGS. 1-5, an embodiment of a tread assembly 10 isillustrated. In some embodiments, the tread assembly 10 includes a frame20 and a tread 60. In some embodiments, the frame 20 is generally rigid.In some cases, the frame 20 is made of metal (e.g., steel or aluminum)or a polymer (e.g., nylon). The frame 20 and/or tread 60 can include arotational centerline. In some embodiments, as illustrated in FIG. 2,the rotational centerline L of the frame 20 is collinear with therotational centerline of the tread 60 when the frame 20 is mated withthe tread 60.

As shown in FIG. 3, the frame 20 can be configured to engage with thetread 60. The frame 20 can have one or more recessed features 23. Forexample, in the embodiment illustrated, the frame 20 can includerecessed features 23 that are arranged in a radial pattern around anouter circumference of the frame 20. As will be discussed in furtherdetail below, the recessed features 23 can engage with correspondingfeatures of the tread, thereby securing the frame 20 and the tread 60.

According to some variants, the frame 20 includes a hub-engaging surface28 located on the radially-inward surface of the frame 20. The frame 20can include first mating features 22. In some embodiments, the firstmating features 22 are located on the hub-engaging surface 28. Incertain variants, such as is shown in FIGS. 3 and 4, the first matingfeatures 22 can be one or more radially inwardly-extending flanges 24.In some embodiments, first mating features 22 are configured to allowfor the insertion of a corresponding number of fasteners, such as onefastener per first mating feature 22. In the illustrated embodiment, thefirst mating features 22 are generally equally spaced in a radialpattern around an inner periphery of the frame 20. However, otherconfigurations are contemplated and are included in this disclosure.

In some embodiments, the frame 20 includes indentations 25. In certaininstances, the indentations 25 are arranged in a radial pattern aroundthe inner circumference of the frame 20. One or more of the indentations25 can span the axial (e.g., parallel to the rotational centerline ofthe frame) width W of the hub-engaging surface 28. In some embodiments,one or more of the indentations 25 are located axially-adjacent to theradially inwardly-extending flanges 24. In such embodiments, the firstmating features 22 can comprise a radially inwardly-extending flange 24and an indentation 25. The radially inwardly-extending flange 24 andcorresponding indentation 25 can each have an axial width that is lessthan the axial width W of the hub-engaging surface 28.

The tread 60, or parts thereof, can be made of most any material, suchas rubber, plastic, wood, metal, or otherwise. For example, the tread 60can be a thermo-set material. The tread 60 can be molded onto, injected,fused, welded, or otherwise joined with the frame 20. In some cases, thetread 60 is formed separately from the frame 20 and then coupled withthe frame 20. In other cases, the tread 60 is formed with the frame 20.For example, the frame 20 can be molded during substantially the sameoperation (e.g., injection molding operation) as the tread 60. Incertain instances, the tread 60 covers all exposed outside surfaces ofthe frame 20. In some embodiments, the tread 60 is injection molded ontothe frame 20. In certain cases, the tread 60 is secured with/to theframe 20 by adhering with the indentation features 23.

In some implementations, the tread 60 engages with recesses 26 on theframe 20. For example, the tread 60 can extend around a portion of thesidewall of the frame 20, such that the tread 60 is located radiallyoutward of the frame 20 and a portion of the tread 60 is engaged withthe recess 26. In certain variants, the tread 60 wraps around a portionof the frame 20. In certain instances, the tread 60 is joined with theframe 20 with an adhesive (e.g., glue or epoxy), thermal or sonicwelding, or otherwise. For example, an adhesive can be applied to anouter surface of the frame 20 and/or an inner surface of the tread 60.In some embodiments, the outer surface (e.g., tread-engaging surface) ofthe frame 20 and/or an inner surface (e.g., structure-engaging surface)of the tread 60 can be textured (e.g., dimpled, ribbed, grooved, orotherwise), which can facilitate a connection between the frame 20 andthe tread 60.

The tread 60 can include a traction surface 62 configured to engage witha floor or other surface when the non-motorized vehicle (e.g., ashopping cart) is moved. The traction surface 62 can be constructed ofthe same material as the tread 60 or from a difference material. In someembodiments, the traction surface 62 includes friction features (e.g.,channels, protrusions, etc.) configured to facilitate grip between thetraction surface 62 and the floor on which it is resting.

With regard to FIGS. 6-9, an embodiment of a housing assembly 70 isillustrated. As shown, the housing assembly 70 can include a structuralhub 80 and a cover 90. In certain embodiments, the hub 80 and the cover90 can be assembled together. For example, the hub 80 and cover 90 canbe held together by fasteners 50, which can be arranged in a radialpattern around the circumference of the hub 80 and/or cover 90. In someembodiments, the fasteners 50 engage with radially outwardly-extendingflanges 84, 94 on the hub 80 and cover 90 respectively. For example, oneor more flanges 94 on the cover 90 can be aligned with one or moreflanges 84 on the hub 80 such that a fastener 50 can be extended throughapertures in the aligned flanges 84, 94. In some embodiments, theflanges 94 on the cover 90 are symmetrically distributed about the outercircumference of the cover 90. In some such embodiments, the cover 90can be attached to the hub 80 in a plurality of relative rotationalorientations. In some embodiments, the flanges 94 are asymmetricallydistributed about the outer circumference of the cover 90 such that thecover 90 connects with the hub 80 in only one relative rotationalorientation. In some such embodiments, rotational alignment of someportion of the hub 80 and/or the contents therein can be consistentlyaligned with some portion of the cover 90. In some embodiments, the hub80 and/or cover 90 can include one or more magnets housed within and/oron the surface of the hub 80 and/or cover 90 (e.g., magnets for use withHall effect sensors to activate the electrical components within oraround the housing assembly 70).

In some instances, the hub 80 and/or the cover 90 include second matingfeatures 82. The second mating features 82 can correspond to thefeatures 22 on the inside of the frame 20 of the tread assembly 10. Theillustrated embodiment includes a plurality of second mating features 82arranged in a radial pattern around the outer circumference of thehousing assembly 70. Other configurations are also contemplated and arepart of this disclosure. In some instances, the second mating features82 include radially outwardly extending flanges 84. In some instances,the second mating features 82 include radially inwardly extendingnotches 85. In some instances, such as in the illustrated embodiment,the second mating features 82 include a combination of radiallyoutwardly extending flanges 84 and radially inwardly extending notches85.

As shown, the housing assembly 70 can have an axial depth D. In somecases, the second mating features 82 extend less than the entire axialdepth D of the housing assembly 70. In other cases, the second matingfeatures 82 can extend less than the entire axial depth D of the housingassembly 70. Such a configuration can, for example, provide an improvedconnection between the housing assembly 70 and the tread assembly 10when assembled together, as is discussed below. In some implementations,the depth D of the housing 70 is greater than or equal to the axialwidth W of the frame 20.

In some embodiments, the cover 90 and the hub 80 include rib features 97and 87 that form a mating channel structure around the insidecircumference of the cover 90 and the hub 80. The rib features 97 and 87can house a seal (e.g., a rubber or polymeric O-ring), which can beconfigured to inhibit or prevent moisture or other contaminants fromentering the inside of the housing assembly 70 when the hub 80 isassembled with the cover 90. Such a configuration can, for example,protect devices (e.g., mechanical or electrical components) disposedinside the housing assembly 70. Examples of such devices can include,for example, a brake mechanism, a two-way communication device, anavigation device, a power generator, a computer processor, a battery,combinations of such devices, or otherwise. Examples of some suchdevices are discussed in the following: U.S. Pat. No. 8,046,160, titled“NAVIGATION SYSTEMS AND METHODS FOR WHEELED OBJECTS”; U.S. PatentApplication Publication No. 2006/0244588, filed Mar. 20, 2006, titled“TWO-WAY COMMUNICATION SYSTEM FOR TRACKING LOCATIONS AND STATUSES OFWHEELED VEHICLES”; and U.S. Patent Application Publication No.2006/0249320, filed Mar. 20, 2006, titled “POWER GENERATION SYSTEMS ANDMETHODS FOR WHEELED OBJECTS;” the entirety of each of which is herebyincorporated by reference herein for all it discloses.

In certain variants, the cover 90 and the hub 80 are configured to bereadily separable from each other. For example, in some implementations,the cover 90 and the hub 80 are configured to be separable after thefasteners 50 are removed. Designs including a separable cover 90 and hub80 can, for example, facilitate the ability to service, replace, repair,and/or otherwise attend-to the devices in the housing assembly 70. Forexample, such designs can facilitate installing a new battery in thehousing assembly 70. Some embodiments have an O-ring or other type ofsealing device disposed between, near, or adjacent to the rib features97 and 87.

In some variants, the cover 90 and the hub 80 are substantiallypermanently joined. For example, in some embodiments, the channelstructure can be at least partly filled with an adhesive (not shown)that, in combination with the surfaces formed by rib features 97 and 87,substantially permanently joins the cover 90 and the hub 80. In someembodiments, the adhesive forms a portion of the seal between the cover90 and the hub 80. Further, in some such embodiments, the adhesive caninhibit or otherwise discourage disassembly of the housing assembly 70.

Certain embodiments that have substantially permanently joined cover 90and hub 80 have a longer life expectancy than embodiments in which thecover 90 and the hub 80 are readily separable. For example, embodimentsin which the cover 90 and the hub 80 are substantially permanentlyjoined can include a battery having a greater life expectancy, aninternal generator and power storage (such as is described in U.S.Patent Application Publication No. 2006/0249320, incorporated byreference herein), and/or intelligent power management circuitsutilizing motion sensors, each of which, alone or in combination, canprovide a longer life than embodiments in which the cover 90 and the hub80 are readily separable.

As shown in the exploded views of FIGS. 9-11, the tread assembly 10 canbe installed on the housing assembly 70. For example, the first matingfeatures 22 of the frame 20 can be aligned with the second matingfeatures 82 of the cover 80 and hub 90 of the housing assembly 70. Incertain embodiments, the tread assembly 10 can be axially slidablymounted on the housing assembly 70 when the tread assembly 10 andhousing assembly 70 are moved toward one another in an axial directionAD. In certain such embodiments, the first mating features 22 can bereceived in the radially inwardly extending notches 85 of the housingassembly 70, thus providing a circumferential interference, which caninhibit or prevent the tread assembly 10 from rotating relative to thehousing assembly 70. In some embodiments, the flanges 84 are receivedinto the indentations 25 of the frame 20 to provide additional oralternative circumferential interference between the housing assembly 70and the tread assembly 10. The first mating features 22 and secondmating features 82 can be circumferentially distributed in a symmetricpattern such that the tread assembly 10 can align with the housingassembly 70 in a plurality of relative rotational orientations. In someembodiments, the first mating features 22 and second mating features 82are asymmetrically circumferentially distributed such that the treadassembly 10 and housing assembly 70 can align in only one relativerotational orientation. In some such embodiments, alignment betweencertain features (e.g., sensors, mechanical components, electricalcomponents, etc.) within the housing assembly 70 and certain features ofthe tread assembly 10 can be facilitated.

In some embodiments, as illustrated in FIG. 2A, the tread 60 and/orframe 20 can include one or more mating identifiers 68. The matingidentifiers 68 can facilitate proper orientation of the tread assembly10 with respect to the housing assembly 70 for connecting the treadassembly 10 to the housing assembly 70. For example, mating identifiers68 can be located on the side of the tread 60 that faces the housingassembly 70 before the tread assembly 10 is received onto the housingassembly 70. In some embodiments, the mating identifiers 68 correspondto the side of the tread assembly 10 opposite the inwardly-extendingflanges 24.

In some embodiments, the tread assembly 10 is secured with the housingassembly 70 with fasteners 52 in order to, for example, reduce thechance of unintentional separation and/or to reduce vibration. In someconfigurations, the housing assembly 70 and/or the tread assembly 10include indicia to indicate the fasteners 52 that couple the housingassembly 70 with the tread assembly 10. In certain instances, at leastone of the fasteners 52 is configured to discourage tampering with thewheel assembly. For example, at least one of the fasteners 52 can have anon-standard screw driving connection (e.g., a tamper-resistant head).The fasteners 52 can be installed into the tread assembly 10 and housingassembly along the axial direction AD.

In some embodiments, a method of installing a tread assembly 10 includessliding the tread assembly 10 onto the housing assembly 70. In certaininstances, the tread assembly 10 is slid until it is generally fullyseated on the housing assembly 70 (e.g., in contact with a positive stopor other feature to denote proper placement). The hub 80 can include oneor more hub orientation features 83, such as one or more protrusions 83or recesses. In some such embodiments, the tread 60 and/or frame 20 caninclude one or more tread orientation features 27 (e.g., protrusionsand/or recesses) configured to engage with the one or more huborientation features 83. Engagement between the tread orientationfeatures 27 and the hub orientation feature 83 can facilitate alignmentbetween the first mating feature 22 and the second mating feature 82. Insome cases, the tread assembly 10 is axially installed (e.g., bysliding) onto the housing assembly 70. In some embodiments, the methodincludes securing the tread assembly 10 to corresponding features on thehub 80 with fasteners 52. According to some variants, the tread assembly10 can be connected with and disconnected from the housing assembly 70without unsealing the housing assembly 70 (e.g., without removing thecover 90 from the hub 80).

In certain embodiments, the method further includes mounting the wheelassembly with a caster 240, for example as shown in FIG. 12. In certainembodiments, the method also includes placing the wheel assembly betweenend portions 242 of the caster 240; placing a first fastener 228 (e.g.,a bolt) through the end portions 242 and the wheel assembly; andsecuring the first fastener 228 with a second fastener 232 (e.g., anut). In certain instances, the method also includes mating at least oneflat portion 235 of an axle 234 of the wheel assembly with a retainingclip 225. In certain such cases, the method also includes inhibitingrotation of the axle 234. For example, rotation of the axle 234 can beinhibited by an interference fit between the “U”-shaped side of theretaining clip 225 and at least one of the end portions 242 of thecaster 240.

In some embodiments, a method of removing a tread assembly 10 includessubstantially the reverse of some of the actions in the above-describedmethod of installing a tread assembly 10. For example: separating thewheel assembly from the caster 240 (e.g., by loosening fastener 228,232and removing the fastener 228), loosening the fasteners 52, and axiallysliding the tread assembly 10 off of the housing assembly 70.

In some embodiments, a method of manufacturing a tread assembly 10includes forming a frame 20 and molding a tread 60 onto the frame 20.Some embodiments include vulcanizing the tread 60. In some cases, themethod includes applying an adhesive to an outer surface of the frame20, which can, for example, improve adherence of the tread 60 with theframe 20.

With regard to FIGS. 13-22, another embodiment of a tread assembly isillustrated. In some embodiments, the tread assembly 110 includes aframe 120 and a tread 160. Certain embodiments of the frame 120 arenylon and are injection molded. In some embodiments, the tread 160 isrubber (e.g., ethylene propylene diene monomer (EPDM)). Certain variantsof the tread 160 can be over-molded onto the insert ring 120. As shownin FIG. 14, in the assembled tread 110, the tread 160 can be positionedgenerally outside and around the frame 120. For example, the frame 120can be received in the tread 160.

As illustrated in FIGS. 14-16, in certain implementations, the treadinsert component 120 has first mating features 122 arranged in a radialpattern and spaced apart from one another in a circumferential directionD_(C) around an inside circumference of the frame 120. In some variants,the first mating features 122 correspond to second mating features 182located on an outer circumference of a wheel hub 180. The second matingfeatures 182 can be arranged in a radial pattern around thecircumference of the hub 180. The tread assembly illustrated in FIGS.13-22 includes a wheel cover configured to mate with the hub 180 that isnot shown in the figures. The wheel cover can be configured to mate withthe hub 180 to create a seal between the wheel cover and the hub 180. Insome embodiments, the first mating features 122 and second matingfeatures 182 are asymmetrically circumferentially distributed such thatthe tread insert component 120 and hub 180 can align in only onerelative rotational orientation. In some such embodiments, alignmentbetween certain features (e.g., sensors, mechanical components,electrical components, etc.) of the hub 180 and certain features of theframe 120 and/or tread 160 can be facilitated. The first mating features122 and second mating features 182 can, in some embodiments, becircumferentially distributed in a symmetric pattern such that theinsert component 120 can align with the hub 180 in a plurality ofrelative rotational orientations.

As shown in FIGS. 17 and 18, in some variants, the first mating features122 of the frame 120 include protrusions 124 and recesses 125. Incertain embodiments, the second mating features 182 of the hub 180include recesses 185 and protrusions 184. The first mating features 122can be configured and arranged in such a way that the protrusions 124can be received in the recesses 185 on the hub 180, thereby allowing themating engagement of the protrusions 124 and the recesses 185.Similarly, the protrusions 184 on the hub 180 can be received in therecesses 125 on the insert ring 120, thereby allowing the matingengagement of the protrusions 184 and the recesses 125.

In certain embodiments, the tread insert 160 can be assembled with thewheel hub 180 by mating (e.g., by sliding) the tread insert 160 onto thehub 180. For example, the protrusion 124 on the insert 160 can begenerally aligned with a portion of the recess 185 of the hub 180,thereby allowing the protrusion 124 to be slidably received (e.g.,axially) in the recess 185. In some embodiments, the insert 160 ispushed onto the hub 180. In some embodiments, the tread insert 160 ispushed completely onto the hub.

In certain variants, the recess 185 has sufficient axial width (e.g.,parallel with the axis of rotation) that the protrusion 124 does notcircumferentially interfere with the protrusion 184, when the protrusion124 is received in the recess 185. In some arrangements, when theprotrusion 124 is received in the recess 185, the protrusion 124 has afirst axial width and the protrusion 184 has a second axial width, withthe first and second axial widths not axially overlapping.

As shown in FIGS. 21 and 22, in some implementations, the tread insert160 can be rotated relative to the hub 180. In some embodiments, thetread insert 160 can be rotated (e.g., in a clockwise direction relativeto the hub) until it engages (e.g., abuts or otherwise is stopped by)walls that define the recess 185 of the hub 180. For example, rotationof the tread insert 160 relative to the hub 180 can cause the protrusion124 of the insert 160 to be received into a second recess 188 extendingperpendicular and generally in a circumferential direction D_(C) awayfrom the recess 185. In some configurations, rotation of the treadinsert 160 relative to the hub 180 can cause the protrusion 184 of thehub 80 to be received into the second recess 129 on the tread insert120. Such a configuration can, for example, increase the strength and/orreduce the likelihood of relative movement of the insert 160 and hub180. In some embodiments, the engagement of the insert 160 and the wallsof the hub 180 facilitates torque transfer between the insert 160 andthe hub 180. In certain variants, when the tread insert 160 is rotated,the protrusions 124 on the inside circumference are moved near, next to,in front of, and/or behind the protrusions 184 on the outside of the hub180.

In certain implementations, the protrusions 124, 184 include holes 111.In certain embodiments, when the tread insert component 160 has beenrotated to its final position, the holes 111 that pass through each ofthe protrusions 124, 184 will be aligned. In some implementations,fasteners (e.g., screws 52) can be driven into the aligned holes 111,thereby securing the tread insert 160 and hub 180 and/or inhibiting orpreventing further relative rotation of the insert 160 and hub 180. Somevariants include a wheel cover with a mating hole (not shown). In someembodiments, the fasteners 50, 52 secure the tread insert 160 and hub180 and wheel cover (not shown). For example, the fasteners 50, 52 canpass through a portion of each of the tread insert 160 and hub 180 andwheel cover. Such a configuration can enhance the structural and/orwatertight characteristics of the tread assembly. In some embodiments,each of the fasteners 50, 52 passes through the wheel cover. In someembodiments, the fasteners 52 used to connect the first mating feature122 to the second mating feature 182 can have a non-standard screwdriving connection (e.g., a tamper-resistant head).

In some embodiments, the tread insert 160 can be configured such thatthe protrusion 124 can be axially spaced apart from the protrusion 184.In some variations, the protrusion 124 of the tread insert 106 arereceived by a generally axially oriented third recess 189 of the secondmating feature 182. Such reception of the protrusions 124 can facilitatetorque transfer between the protrusion 124 and the walls defining thethird recess 189. In some embodiments, engagement of the protrusion 124with the third recess 189 can reduce stress on any fasteners 52 used tomate the first mating feature 122 with the second mating feature 182.

Although the present disclosure has been described in terms of certainpreferred embodiments and certain preferred uses, other embodiments andother uses that are apparent to those of ordinary skill in the art,including embodiments and uses which do not provide all of the featuresand advantages set forth herein, are also within the scope of thepresent disclosure. Components, elements, features, acts, or steps canbe arranged or performed differently than described and components,elements, features, acts, or steps can be combined, merged, added, orleft out in various embodiments. For example, any or all of the featuresof the tread assembly of FIGS. 1-12 can be used with the tread assemblyof FIGS. 13-22, and any or all of the features of the tread assembly ofFIGS. 13-22 can be used with the tread assembly of FIGS. 1-12. Also, thewheels and tread assemblies shown and described herein can be used onany type of non-motorized wheeled vehicle, human-propelled vehicle, orcart such as a shopping cart, a hospital or medical device cart,wheelchair, an equipment cart, and so forth. Indeed, all possiblecombinations and subcombinations of elements and components describedherein are intended to be included in this disclosure. No single featureor group of features is necessary or indispensable for every embodiment.Accordingly, the scope of certain embodiments of the present disclosureis to be defined by the claims that follow and their obviousmodifications and equivalents.

Certain features that are described in this specification in the contextof separate implementations also can be implemented in combination in asingle implementation. Conversely, various features that are describedin the context of a single implementation also can be implemented inmultiple implementations separately or in any suitable subcombination.Moreover, although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Conditional language used herein, such as, among others, “can,” “could,”“might,” “may,” “e.g.,” and the like, unless specifically statedotherwise, or otherwise understood within the context as used, isgenerally intended to convey that certain embodiments include, whileother embodiments do not include, certain features, elements and/orsteps. Thus, such conditional language is not generally intended toimply that features, elements and/or steps are in any way required forone or more embodiments or that one or more embodiments necessarilyinclude logic for deciding, with or without author input or prompting,whether these features, elements and/or steps are included or are to beperformed in any particular embodiment. The terms “comprising,”“including,” “having,” and the like are synonymous and are usedinclusively, in an open-ended fashion, and do not exclude additionalelements, features, acts, operations, and so forth. Also, the term “or”is used in its inclusive sense (and not in its exclusive sense) so thatwhen used, for example, to connect a list of elements, the term “or”means one, some, or all of the elements in the list.

Conjunctive language such as the phrase “at least one of X, Y and Z,”unless specifically stated otherwise, is otherwise understood with thecontext as used in general to convey that an item, term, etc. may beeither X, Y or Z. Thus, such conjunctive language is not generallyintended to imply that certain embodiments require at least one of X, atleast one of Y and at least one of Z to each be present.

Similarly, while operations may be depicted in the drawings or describedin the specification in a particular order, it is to be recognized thatsuch operations need not be performed in the particular order shown orin sequential order, or that all operations be performed, to achievedesirable results. Other operations that are not depicted or describedcan be incorporated in the example methods and processes. For example,one or more additional operations can be performed before, after,simultaneously, or between any of the described operations.Additionally, the operations may be rearranged or reordered in otherimplementations. Moreover, the separation of various system componentsin the implementations described above should not be understood asrequiring such separation in all implementations, and it should beunderstood that the described components and systems can generally beintegrated together in a single product or packaged into multipleproducts. Additionally, other implementations are within the scope ofthe following claims. In some cases, the actions recited in the claimscan be performed in a different order and still achieve desirableresults.

The following is claimed:
 1. A wheel for a human-propelled cart, thewheel comprising: a housing assembly comprising a hub, the hubcomprising a frame engaging surface having a frame mating feature, theframe mating feature comprising a radially inward recess and a radiallyoutward flange; a tread assembly configured to axially receive a portionof the housing assembly, the tread assembly comprising a frame and atread, wherein: the frame comprises a radially outward tread engagingsurface and a radially inward hub engaging surface, the hub engagingsurface having a hub mating feature and being configured to releasablyengage with the frame engaging surface of the hub, the hub matingfeature comprising: a radially inward flange configured to engage withthe radially inward recess of the housing assembly, wherein the radiallyinward flange of the frame has an axial length that is less than orequal to an axial length of the radially inward recess of the housingassembly, and a radially outward recess configured to engage with theradially outward flange of the housing assembly, wherein the radiallyoutward recess of the frame has an axial length that is greater than orequal to an axial length of the radially outward flange of the housingassembly, the tread is disposed radially outward of the frame andengaged with the tread engaging surface, an exterior of the treadconfigured to contact a surface on which the wheel is configured toroll; and wherein the tread assembly is configured to removably couplewith the housing assembly such that the tread assembly can be axiallyseparated from the housing assembly, and wherein, when the hub engagingsurface of the frame is engaged with the frame engaging surface of thehub, the frame mating feature and the hub mating feature arecircumferentially aligned such that a fastener can engage the framemating feature and the hub mating feature.
 2. The wheel of claim 1,wherein the housing assembly further comprises a plurality of huborientation features and the tread further comprises a plurality oftread orientation features, the plurality of hub orientation featuresconfigured to engage with the plurality of tread orientation features.3. The wheel of claim 2, wherein the plurality of hub orientationfeatures comprise axially extending projections and the plurality oftread orientation features comprise axially extending recessesconfigured to receive the projections.
 4. The wheel of claim 1, furthercomprising a cover configured to sealingly connect with the hub.
 5. Thewheel of claim 4, wherein: the cover comprises a plurality of radiallyinwardly extending recesses; and when the cover is connected with thehousing assembly, the radially inwardly extending recesses of the covercircumferentially align with the radially inwardly extending recesses ofthe hub.
 6. The wheel of claim 4, further comprising one or moreelectronic components disposed in the hub.
 7. The wheel of claim 1,wherein the human-propelled cart is a shopping cart.
 8. The wheel ofclaim 1, further comprising the fastener.
 9. A tread assembly axiallyengagable with a wheel for a human-propelled cart, the wheel comprisinga hub having a plurality of axially extending tabs, the tread assemblycomprising: an annular frame comprising a radially inner surface and aradially outer surface, the radially inner surface of the frameconfigured to engage with the hub of the wheel; and a tread comprising aradially inner surface and a radially outer surface connected by asidewall, wherein: the radially inner surface of the tread is engagedwith the radially outer surface of the frame; the radially outer surfaceof the tread is configured to contact a surface on which the wheelrolls; and the sidewall comprises a plurality of axially extendingrecesses, the recesses being configured to receive the tabs of the hub,thereby facilitating orientation of the tread relative to the frame andinhibiting rotation of the tread assembly relative to the hub.
 10. Thetread assembly of claim 9, wherein the radially inner surface of theframe further comprises a plurality of indentations, the plurality ofindentations of the frame being circumferentially aligned with therecesses of the tread.
 11. The wheel of claim 10, wherein theindentations of the frame receive the recesses of the tread.
 12. Thewheel of claim 11, wherein the plurality of indentations do not extendfrom the radially inner surface of the frame to the radially outersurface of the frame.
 13. The wheel of claim 12, wherein the framefurther comprises a sidewall, the plurality of indentations extendingthrough the sidewall of the frame.
 14. A wheel for a human-propelledcart, the wheel comprising the tread assembly of claim 9 and the hub.15. A wheel for a shopping cart, the wheel configured to rotate about anaxis and to roll on a surface, the wheel comprising: a housing assemblyconfigured to couple with the shopping cart via a caster assembly; asealed chamber located in the housing assembly; an electrical componentpositioned in the sealed chamber; a tread assembly coupled with thehousing assembly, the tread assembly configured to engage the surface onwhich the wheel rolls, the tread assembly comprising an annular frameand a tread; and a plurality of fasteners movable between a tightenedstate and a loosened state, the fasteners configured to engage thehousing assembly and the tread assembly; wherein, when at least one ofthe fasteners is in the tightened state, the tread assembly and thehousing assembly are secured with each other; and wherein, when each ofthe fasteners are in the loosened state, the tread assembly can betranslated relative to the housing assembly along the axis, therebyallowing the tread axially to be axially separated from the housingassembly without opening the sealed chamber.
 16. The wheel of claim 15,wherein the tread assembly further comprises first flanges and thehousing assembly further comprises first recesses, the first flangesconfigured to be received in the first recesses.
 17. The wheel of claim15, wherein the fasteners are positioned around a circumferentialperiphery of the wheel.
 18. The wheel of claim 15, wherein, when each ofthe fasteners are in the loosened state, the tread assembly can also berotated relative to the housing assembly about the axis.
 19. The wheelof claim 15, wherein, each of the fasteners engage the housing assemblyand the tread assembly from the same axial side of the wheel.
 20. Thewheel of claim 15, further comprising the caster assembly.